Final answer:
In foggy conditions, low beam headlights should be used to provide better visibility and to reduce glare that can be caused by high beams reflecting off the fog.
Step-by-step explanation:
When driving in a fog, you should use low beam headlights on your car. Low beams are designed to point down towards the road and reduce the glare caused by fog, rain, or snow.
Turning on the high beams in a fog can actually be counterproductive as the light reflects off the fog and creates a glare, making it harder for you to see and for other drivers to see you.
The design of headlights, as demonstrated in the concept of trapped light forming a directional beam, is crucial in these circumstances.
Modern headlights are often designed to better manage the heat dissipation and power consumption as part of their efficiency.